Refactor error handling

src/sys/mod.rs

@@ -6,17 +6,27 @@ cfg_if! {
  mod unix;
  pub use self::unix::*;
 
- pub fn errno_from_host(err: i32) -> host::__wasi_errno_t {
+ pub(crate) fn errno_from_host(err: i32) -> host::__wasi_errno_t {
  host_impl::errno_from_nix(nix::errno::from_i32(err))
  }
  } else if #[cfg(windows)] {
  mod windows;
  pub use self::windows::*;
 
- pub fn errno_from_host(err: i32) -> host::__wasi_errno_t {
+ pub(crate) fn errno_from_host(err: i32) -> host::__wasi_errno_t {
  host_impl::errno_from_win(winx::winerror::WinError::from_u32(err as u32))
  }
  } else {
  compile_error!("wasi-common doesn't compile for this platform yet");
  }
 }
+
+pub(crate) fn errno_from_ioerror(e: std::io::Error) -> host::__wasi_errno_t {
+ match e.raw_os_error() {
+ Some(code) => errno_from_host(code),
+ None => {
+ log::debug!("Inconvertible OS error: {}", e);
+ host::__WASI_EIO
+ }
+ }
+}

src/sys/unix/hostcalls_impl/fs.rs

@@ -4,15 +4,14 @@ use super::fs_helpers::*;
 use crate::ctx::WasiCtx;
 use crate::fdentry::FdEntry;
 use crate::helpers::systemtime_to_timestamp;
-use crate::sys::errno_from_host;
 use crate::sys::fdentry_impl::determine_type_rights;
 use crate::sys::host_impl;
+use crate::sys::{errno_from_host, errno_from_ioerror};
 use crate::{host, wasm32, Result};
 use nix::libc::{self, c_long, c_void, off_t};
 use std::convert::TryInto;
 use std::ffi::CString;
 use std::fs::{File, Metadata};
-use std::io;
 use std::os::unix::fs::FileExt;
 use std::os::unix::prelude::{AsRawFd, FromRawFd};
 
@@ -362,12 +361,7 @@ pub(crate) fn path_rename(
 pub(crate) fn fd_filestat_get_impl(file: &std::fs::File) -> Result<host::__wasi_filestat_t> {
  use std::os::unix::fs::MetadataExt;
 
- fn convert_err(e: io::Error) -> host::__wasi_errno_t {
- log::debug!("fd_filestat_get: os error: {}", e);
- e.raw_os_error().map_or(host::__WASI_EIO, errno_from_host)
- }
-
- let metadata = file.metadata().map_err(convert_err)?;
+ let metadata = file.metadata().map_err(errno_from_ioerror)?;
  Ok(host::__wasi_filestat_t {
  st_dev: metadata.dev(),
  st_ino: metadata.ino(),
@@ -378,15 +372,15 @@ pub(crate) fn fd_filestat_get_impl(file: &std::fs::File) -> Result<host::__wasi_
  st_size: metadata.len(),
  st_atim: metadata
  .accessed()
- .map_err(convert_err)
+ .map_err(errno_from_ioerror)
  .and_then(systemtime_to_timestamp)?,
  st_ctim: metadata
  .ctime()
  .try_into()
  .map_err(|_| host::__WASI_EOVERFLOW)?, // i64 doesn't fit into u64
  st_mtim: metadata
  .modified()
- .map_err(convert_err)
+ .map_err(errno_from_ioerror)
  .and_then(systemtime_to_timestamp)?,
  st_filetype: filetype(&metadata),
  })

src/sys/windows/hostcalls_impl/fs.rs

@@ -4,7 +4,7 @@ use super::fs_helpers::*;
 use crate::ctx::WasiCtx;
 use crate::fdentry::FdEntry;
 use crate::helpers::systemtime_to_timestamp;
-use crate::sys::errno_from_host;
+use crate::sys::{errno_from_ioerror, errno_from_host};
 use crate::sys::fdentry_impl::determine_type_rights;
 use crate::sys::host_impl;
 use crate::{host, Result};
@@ -196,33 +196,28 @@ pub(crate) fn change_time(file: &File, _metadata: &Metadata) -> io::Result<i64>
 }
 
 pub(crate) fn fd_filestat_get_impl(file: &std::fs::File) -> Result<host::__wasi_filestat_t> {
- fn convert_err(e: io::Error) -> host::__wasi_errno_t {
- log::debug!("fd_filestat_get: os error: {}", e);
- e.raw_os_error().map_or(host::__WASI_EIO, errno_from_host)
- }
-
- let metadata = file.metadata().map_err(convert_err)?;
+ let metadata = file.metadata().map_err(errno_from_ioerror)?;
  Ok(host::__wasi_filestat_t {
- st_dev: device_id(file, &metadata).map_err(convert_err)?,
- st_ino: file_serial_no(file, &metadata).map_err(convert_err)?,
+ st_dev: device_id(file, &metadata).map_err(errno_from_ioerror)?,
+ st_ino: file_serial_no(file, &metadata).map_err(errno_from_ioerror)?,
  st_nlink: num_hardlinks(file, &metadata)
- .map_err(convert_err)?
+ .map_err(errno_from_ioerror)?
  .try_into()
  .map_err(|_| host::__WASI_EOVERFLOW)?, // u64 doesn't fit into u32
  st_size: metadata.len(),
  st_atim: metadata
  .accessed()
- .map_err(convert_err)
+ .map_err(errno_from_ioerror)
  .and_then(systemtime_to_timestamp)?,
  st_ctim: change_time(file, &metadata)
- .map_err(convert_err)?
+ .map_err(errno_from_ioerror)?
  .try_into()
  .map_err(|_| host::__WASI_EOVERFLOW)?, // i64 doesn't fit into u64
  st_mtim: metadata
  .modified()
- .map_err(convert_err)
+ .map_err(errno_from_ioerror)
  .and_then(systemtime_to_timestamp)?,
- st_filetype: filetype(&metadata).map_err(convert_err)?,
+ st_filetype: filetype(&metadata).map_err(errno_from_ioerror)?,
  })
 }